1. Field of the Invention
The present invention relates to a steering damper control apparatus that controls a damping force of a steering damper provided in a steering device of a vehicle to adjust a damping force, and to a saddle riding type vehicle including the same.
2. Description of the Related Art
Recently, saddle riding type vehicles including a steering damper control apparatus to adjust a damping force of a steering device in order to stabilize posture changes and to ease the riders' burden have been increasing in popularity. Such steering damper control apparatus include the following.
A first apparatus of this type has a steering device, a steering damper, an adjusting mechanism, a rear stroke sensor, and a control device (see Japanese Unexamined Patent Publication No. 2009-126432, for example). The steering device is pivotably supported by a vehicle body. The steering damper applies a damping force to the torque of the steering device. The adjusting mechanism adjusts the damping force of the steering damper. The rear stroke sensor detects an amount of stroke of a rear suspension. Based on outputs of the rear stroke sensor, the control device, when the vehicle is slowing down, controls the adjusting mechanism to increase the damping force of the steering damper compared with a time of steady traveling.
This first apparatus, when the vehicle is determined to be slowing down based on the outputs of the rear stroke sensor, increases the damping force of the steering damper. This can prevent kickbacks produced against the rider's intention by the steering device undergoing disturbance of the traveling surface, for example. As a result, posture changes of the vehicle can be prevented even when the vehicle is slowing down.
A second apparatus of this type includes a steering damper which adjusts a damping force according to an amount of operation of the accelerator. When an opening degree of the accelerator is small, the vehicle is determined to be traveling at low speed, and the damping force is kept low. When the opening degree of the accelerator is large, the vehicle is determined to be traveling at high speed, and the damping force is increased (see Japanese Unexamined Patent Publication No. 2001-301682, for example).
This second apparatus determines a traveling state based on the amount of operation of the accelerator, thus preventing the steering device from becoming unstable which would easily produce a situation where the front wheel is subject to levitation. As a result of this determination, posture changes of the vehicle can be prevented during acceleration.
A third apparatus of this type includes an acceleration detector and a control device (see Japanese Unexamined Patent Publication No. 2002-302085, for example). The acceleration detector detects acceleration of the vehicle body. Only when the acceleration exceeds a threshold value, the control device causes a steering damper to generate a damping force.
Although a load of the front wheel will decrease to produce a kickback easily when acceleration reaches or exceeds the threshold value, this third apparatus can increase the damping force of the steering damper to prevent a kickback. As a result, posture changes of the vehicle can be prevented during acceleration.